Dental matrix and retainer therefor



April 28, 1953 R. l.. swEETEN 2,636,269

DENTAL MATRIX .AND RETAINER THEREFOR Filed Feb. 21; 1952 Snoentor w Gttorneg Patented Apr. 28, 1953 UNITED STATES PATENT OFFICE,

DENTAL MATRIX AND RETAINER THEREFOR Robert L. Sweeten, Salt Lake City, Utah Application February 21, 1952, Serial No. 272,757

This invention relates to a dental matrix and retainer therefor, and more specifically to a matrix retainer especially designed to facilitate Vthe filling of cavities in the approxim-al, as well as the inner` and outer sides of natural teeth.

One of the primary objects of this invention is to provide a matrix retainer of the type described with means for maintaining the matrix yin position within the interproximal area between a pair of adjacent teeth.

vprovide a dental matrix and retainer of simplied construction and which may be quickly `and easily engaged and disengaged from the teeth while the matrix is in the mouth of the patient.

Another object of this invention is .to provide a device of the type described which may be utilized in conjunction with the lling of cavities in either the upper or lower jaws.

Other and further objects and advantages of the present :invention will become apparent from the following specification when read in light of the annexed drawings, in which:

Fig. 1 is an exploded perspective view of the "matrix and retainer;

Fig. 2 is a side elevation, partly in section, showing the matrix and retainer positioned in the interproximal of a pair of adjacent teeth with the tension clamp applied to the anterior loop;

Fig. 3 is a longitudinal section taken on the line 3-3 of Fig. 1; and

Fig. 4 is an enlarged detail perspective view taken on the line 4-4 of Fig. 1, showing the connection of the threaded shaft with the bar.

Referring now more specically to the drawings. reference numeral 2 indicates, in general, a matrix retainer clamp constructed according to this invention. The clamp 2 comprises an elongated, rectangular metallic base 4 of relatively thin transverse cross-section. One Aof the ends of base 4 is curved to form a socket 6 in which the cylindrical standard 8 is ixedly secured, as by welding. As seen in the drawings, standard 8 is of greater length than the width of base 4 and is positioned with its longitudinal axis substantially perpendicular to the longitudinal axis of base 4.

The other end of base 4 is bent laterally away from base 4 to form one arm II) of a U-shaped bracket I2. The free end of arm I is reversely bent to form the other arm I4 of bracket I2.

5 Claims. (Cl. 32-63) A metallic b-ar I6, also having a relatively .thin `cross-section and of the same width as base 4, is held in sliding engagement with base 4 by clamp I 8. One end of bar IB is curved to form a socket 20 within which is secured, as'by Welding, one end of a second cylindrical standard 22. Standard 22 is of greater length than the Width of the bar I6, and their respective longitudinal axes are perpendicular to each other.

The other end of bar I6 is deflected outwardly from base 4 and is crimped at 2| about .the cone shaped end 23 of a threaded shaft 24. The other end of shaft 24 passes through aperture 26 formed in arm I0 and extends beyond the other arm I4 of bracket I2.

Shaft 24 is threaded through knurled nut 28 having a peripheral groove 30 which receives Ithe free end of arm I4. As is now manifest, rotation of nut 28 will effect an adjustment of cylindrical standard 22 relative to standard 8 in a direction parallel to the longitudinal axis of base 4.

The matrix comprises an endless band 32, 'of thin, flexible, shim steel, which, under operative conditions, is removably mounted around standards 8 and 22.

Having now described in detail the component elements of the matrix and retainer, the operation thereof will be set' forth with particular reference to Fig. 2.

Dental cavities yare indicated by reference numerals 34 and 36 for'med in an adjacentpair of anterior teeth 38 and 4I), respective1yandit will be presumed that the dentist has prepared the teeth to receive a filling material formed of plastic or synthetic porcelain restoratives.

The lling material is then prepared and inserted in the cavities. Thereafter the matrix 32 is pinched together at 4I forming two loops 42 and 44 with loop 42 being approximately one third the size of loop 44. The matrix is then inserted between the interproximal area of the :anterior teeth 38 and 40, with the loop 44 adjacent the anterior side of the teeth. A small piece .46 of hard but elastic material, such as gutt'a'- percha is inserted within the smaller loop 42 posi- 4tioned -on the lingual side.

Standards 8 and 22 are now inserted within loop 44 and nut 28 is rotated separating the standards from each other to tighten the band around the interproximal contour of the teeth, and to compress and retain the filling material in position in the cavities until it has set or hardened. Slippage through the interproximal area of the lingual loop 42 is prevented by the wedging action of element 46 in loop 42 on the lingual side of the teeth.

After the filling material has hardened, nut 28 is rotated to cause standard 22 to move toward standard 8 until they may be removed easily from loop 44, and the retainer 32 together with element 46 lis removed from the interproxmal area between the teeth.

The matrix and retainer may be sterilized easily since the parts thereof are easily assembled andidisassembled, and are .of non-'complex construction.

Having set forth this invention in detail, it will be understood that the instant embodiment has been offered merely for the purpose .of .illustration and that the invention is onlyto'be lim ited by the scope of the following claims.

I claim;

l. A dental matrix and retainer therefor coinprising a thin endless band to 'be disposed in the interproximal area between a pair of adjacent lteeth and forming a loop on the anterioi` and ,lingual sides. of saidteeth, a wedging .element disposed within saidlinguall'oop, and means fior enlarging said anterior loop to tighten said 'loops Varound the `interproxirnal .contour of the teeth.

.2. A. dental matrix and retainer thereforcnmprisinga thin endless band to. be disposed in the interproximal area between ,a pair of' adjacent .teeth and forming a loop on .the anterior and lingual' 4sides thereof, a Wedging element disposed ,withinsaidllingual loop, Vand means ior clamp- .inglsaid 'loops against the anterior and iinguai sides of theteeth, said means comprising a base havinga standard xedly mounted thereonx a second standard vmounted on said base, said standards being detachably positioned Within said anterior loop, and means for moving said sec-ond standard relative to said' first standard to exert tension on said anterior loop to clamp said loops .against the anterior .and vlingual sidesV of said teeth.

'3. A dental matrix and. retainer therefor coniprising a thin endless'bandto be disposed in the interproxi'mal area between a pair of adjacent teeth and 'forming a loop on the anterior` and lingual Asides thereof, means `ior clamping sai-d loops against the anterior and lingua sides lof 'the"teeth, s aidmeans comprising an elongated basel-having a standard at one end thereof, said standard extending 'transversely of said base, `Va

bar slidably mounted on said base, a second standard amxed toY said bar and extending transverselythereof, said'seoond standard beingsubstar-iti'aliyv parallel to said first standard, said standards oeinglpositioned within *saidE .anterior loop, `andineans coacting with said hase and bar for increasing the distance between said stand.- ards fto "exert tension on said anterior l'oop, wlfiereloysaidf anterior and: lingual loopsf are.:` dra-Wn against. their :respective 'adjacent .sides of .said teeth.

:4; Aidentaltmatrix and retainer `therefor lcomprisme .mithin endlessl bandsto he disposed; in. the interproximal area between `a .pairnf adjacent anterieriteeth and forming afloopfontheanterior and :lingual sides thereoh .means for clamping said loops tajgaiizlsty .the anterior 'and lingual sides of said .teeth, said. means comprising .an elon- 4 gated base having a standard at one end thereof, said standard extending transversely of said base and being of greater length than the Width of said base, said base having a laterally extending arm provided with an opening therein, an elongated bar slidably mounted on said hase, a second standard affixed to said bar at one end thereof and extending transversely thereof, said second `standard being Vapprcimately parallel to `saidArstzstandard and v,haring a. length greater than the Width of said base and of said bar, said standards being detachably positioned within said anterior loop, a threaded shaft having one of its 4.ends connected with the other end of said bar, the other end of said shaft extending through said .opening 'formed in said arm, and a threaded nut mounted on the free end of said threaded shaft for moving said standards toward and avi/al7 from each other to increase or decrease tension on said anterior loop.

.5. A. dental matrix andA retainer therefor comprising a thin endless'bantl to'be disposed in the interproximal area vf'ietween a pair o adjacent anterior teeth and `forming a loop on the anterior and lingual'sides thereof, means for clamping.' saidloops adjacent' the anterior and lingual sides of the teeth, said means comprising an elongated 'oase .having a standard at one end thereof, said standard extending transversely of said base andheing of greater length than'the width of said base, a laterally'I projecting arm on the other end of said. base,` saidarm having an opening therein, the free end of said arm being reverseiy curved, a harslid-ably mounted on said hase, guide means securing said base'and said bar in juxtaposed relationship, a second standard afi-"ixed to one end of said bar and Aextending transversely thereof, said second standard being parallel to said'first@stan-dardV and having a length greater thanithe Widthof Lsaid base' and of said har, said stand'ardsbeingdetachably positioned within said anterior loop, a threadedeha-ft 'having one oi its ends -seoured 'to the other end of said bar, the otherend of said- `threaded shaft extending through said opening vformed in said arm, ya nut threaded `on said threaded shaft at the free'end thereof, Asaid nut having a `groove formed in its outer periphery intermedie-tothe endsA thereof, 'saidJ reversel-y curved vend engaging Within said groove to engage opposed sides of saidgroove, wherehyassaid nut is turned one 'direction-Dintherother relative movement between said .standardsl is obtained to increase or decrease thertension; on said anterior loop. ROBERT.' L. .nerereness enea in the-nre or `this patent .lhlllliD STA'IES PATENTS 

